Even though my boat did more sitting this year than it did running I believe I have an issue. Boat is an '86 Seville with the merc 170 and alpha 1. It has the closed cooling system on it. I went to take her out for one last run before winterizing it. Well first the battery was dead. No big deal as I knew it was on its way out. Second after a fluid check all the antifreeze in the closed portion of the cooling system was gone. It was low last time I ran it and I know I filled it. It looks like I need to replace the gaskets on both sides of the holding tank. What else should I look for? I'm a pretty good shade tree mech but admittedly, I don't know s**t about how this thing is set up. One last item is the motor has about 100 hours on it since the rebuild. When I get home I'll see if the risers were replaced as i've only had it for 1 year. Thanks.